For some years now, hamburger sandwiches have been dispensed in foam packaging designed to hold sandwiches in acceptable condition for a predetermined period of time. Typical foam packages are shown in U.S. Pat. Nos. 4,132,344 and 3,902,540. Hamburger sandwiches of various types have been so dispensed by the hundreds of millions. Despite this wide usage, efforts to preassemble and hold sandwiches which include lettuce and tomatoes, or other fresh vegetables, in foam packaging have not been entirely satisfactory. The quality of such preassembled sandwiches when held for even short periods of time has not been as desirable as might be preferred.
A variety of efforts to design packaging for lettuce and tomato hamburger sandwiches have been made, including separating the meat and bun heel in one side of an open clamshell-type foam package and the lettuce, tomato, condiments, and bun crown in the other side of the open clamshell, and then placing them within a sleeve, such as a foam or paperboard sleeve, to contain them and for dispensing. Although there are a number of drawbacks to such packaging, such packaging will hold the sandwich components in acceptable condition for longer than a fully assembled sandwiched may be acceptably held.
Yet there remains the need for suitable packaging which will hold the components of a lettuce and tomato hamburger sandwich for an acceptable length of time, while maintaining desirable temperature and moisture levels of the meat, while maintaining the crispness and freshness of the lettuce and tomato, and while providing suitable convenience for the consumer.